The invention relates to apparatus used by gardeners and, particularly, home gardeners, and commonly referred to as dusters for spraying of insecticidal garden dust or powders onto growing plants, bushes, shrubs and the like. The present application presents specific improvements on a hand duster disclosed in U.S. Pat. No. 3,330,445.
It has been proposed, see U.S. Pat. No. 3,330,445, to combine in a lightweight, portable, hand-operated duster a material hopper for the pulverulent material, a high-speed rotary impeller for propelling the material in a controlled stream for dusting plants and the like, and a manually-operated crank and gear train connected to the impeller for generating the required high-speed rotation thereof. One of the problems encountered is overheating and deterioration of certain high-speed parts. Another problem encountered is that the garden dusts are exceedingly fine and will penetrate and infiltrate bearings, gears and other moving parts and are, at the same time, highly abrasive and, accordingly, abrade and destroy critical moving parts and cause early and premature failure of the structure. Also, certain garden dusts absorb moisture and harden. An uncontrolled build-up of such material in the impeller chamber may break up the impeller.